Brake pad wear indicator light does not go off at the dash after changing rotors brake pads and the sensor in the front wheels all pads and rotors and the sensor is ok at rear. the vehicle has only 30000 KM 2004 BMW Z 4 Roadster with 2.5 litre engine

Did you change the sensor? if you did, do a battery reset (disconnect for 10 to 20 min.).

Obviously the wear sensor has made contact with the rotor and is already damaged. You're not even suppose to resuse the wear pad sensor if its worn or damaged anyways.The way how the sensor works is that it must make contact to the rotor to complete the wear pad light indicator circuit. There is no mentioning that he replaced the the wear pad sensor with a new one.

But if one did replaced the wear pad sensor and the wear pad indicator is lit up, the way to reset it is to leave the key on in ignition switch #2 or #1 for about 30sec. turn it off and its reset.

Its possible that you forgot to replace the brake light sensors. They are about 15 bucks, and have to be replaced in order for that light to turn off. You can either get them from the dealer where they'll likely charge you 3 times as much, or you can go to http://www.turnermotorsport.com and get them there.

You have to reset the light by leaving the ignition switch on position #2 for about 30 sec. turn off the ignition and start the engine up and see if it goes out. I recommend buying a new wear pad sensor as well because now light will lit up when you're way below spec (less than 3mm)

Also, you could try with this procedure for one E39: Turning off the Check Brake Linings warning on the Instrument Cluster...
- so you've just changed the brake pads on your E39, along with the wear sensors. The old sensor(s) needed replacement cause you waited a bit too long before changing the pads, and wore through the sensor(s), turning on the BRAKE light on the dash. But wait, the light is still on? But there's a new sensor installed... what gives?!
- there is a procedure required in order to turn off the light/warning. With the ignition off, step on and hold the brake pedal. Now, while holding the brake pedal down, turn on the ignition switch to position 2 (just before cranking). Hold the brake pedal until the BRAKE light is off. Tada, the warning is gone and reset.

NOTE: This procedure worked on a 2001 E46 325i. It took about 15-20 seconds, but it cleared out w/o having to unhook the battery.

Other details find in the Owners Manual 2006-BMW-Z4m-Roadster-Owner-Manual

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